A blackout refers to a state or a phenomenon in which all power systems stop due to lack of electricity. A blackout generally refers to a large scale power outage situation and a case in which a power outage occurs everywhere in a certain region.
In South Korea, an unprecedented power outage situation suddenly occurred on Sep. 15, 2011 in the whole region of Gangnam and Yeouido, throughout the country including Gyeonggi, Gangwon, Chungchoeng, and the like, excluding Jeju. The power outage situation started at 3:10 p.m. on that day and was normalized at 7:56 p.m. after continuing for five hours, and a power outage scale was a maximum of 1.62 million sites nationally at one time, and the identified amount of damage was 610 billion won.
Accordingly, a system with which power may be effectively controlled for preventing further damage from occurring to industrial facilities, medical facilities, and general homes due to a blackout is required.
Recently, technologies have been actively developed for methods by which power is saved by interrupting standby power and reducing unnecessarily wasted power among methods by which power is effectively controlled.
Standby power refers to a micro power of about one to five W per hour applied to power consuming products, such as refrigerators, electric fans, electric washers, and television sets, due to a current of a plug socket flowing through a plug plugged into an power outlet even when an power switch of the power consuming product is turned off as long as the plug is not separated from the power outlet.
According to statistics, it is known that power loss corresponding to several hundreds of billion won per year occurs due to a wasted micro current.
Generally, an on and off switch may be installed at a multi tap for interrupting a current supply.
However, when a number of power consuming products are connected to one multi tap, there is a problem of aesthetics being spoiled due to complex wiring, and efficiency is lowered due to difficulty in collectively interrupting a current supply.
In addition, a smart grid has been discussed as a method for effectively controlling power.
The smart grid refers to a technology with which energy efficiency is optimized by applying information technology to a conventional one way power grid including a step of power generation and power transmission and a step of power distribution and power sales, and bilaterally exchanging information between an electricity supplier and consumers. The smart grid connects a power plant and power transmission and distribution facilities, and consumers through an information network, and efficiently operates a power system using bilaterally shared information.
However, a communication security problem has become an important issue according to necessity of an additional communication system, and there is a problem of a receiving device cost and a consumer communication fee.